JoVE Visualize What is visualize?
Related JoVE Video
Pubmed Article
Factors influencing early and late mortality in adults with invasive pneumococcal disease in Calgary, Canada: a prospective surveillance study.
PUBLISHED: 01-01-2013
Invasive pneumococcal disease continues to be an important cause of mortality. In Calgary, 60% of deaths occur within 5 days of presenting to hospital. This proportion has not changed since before the era of penicillin. The purpose of this study was to investigate what factors may influence death within 5 days of presentation with pneumococcal disease.
Authors: Malek Saleh, Mohammed R. Abdullah, Christian Schulz, Thomas Kohler, Thomas Pribyl, Inga Jensch, Sven Hammerschmidt.
Published: 02-23-2014
Pneumonia is one of the major health care problems in developing and industrialized countries and is associated with considerable morbidity and mortality. Despite advances in knowledge of this illness, the availability of intensive care units (ICU), and the use of potent antimicrobial agents and effective vaccines, the mortality rates remain high1. Streptococcus pneumoniae is the leading pathogen of community-acquired pneumonia (CAP) and one of the most common causes of bacteremia in humans. This pathogen is equipped with an armamentarium of surface-exposed adhesins and virulence factors contributing to pneumonia and invasive pneumococcal disease (IPD). The assessment of the in vivo role of bacterial fitness or virulence factors is of utmost importance to unravel S. pneumoniae pathogenicity mechanisms. Murine models of pneumonia, bacteremia, and meningitis are being used to determine the impact of pneumococcal factors at different stages of the infection. Here we describe a protocol to monitor in real-time pneumococcal dissemination in mice after intranasal or intraperitoneal infections with bioluminescent bacteria. The results show the multiplication and dissemination of pneumococci in the lower respiratory tract and blood, which can be visualized and evaluated using an imaging system and the accompanying analysis software.
17 Related JoVE Articles!
Play Button
Experimental Human Pneumococcal Carriage
Authors: Jenna F. Gritzfeld, Angie D. Wright, Andrea M. Collins, Shaun H. Pennington, Adam K.A. Wright, Aras Kadioglu, Daniela M. Ferreira, Stephen B. Gordon.
Institutions: Liverpool School of Tropical Medicine, University Hospital Trust, Comprehensive Local Research Network, Royal Liverpool and Broadgreen University Hospitals NHS Trust, University Hospitals of Leicester NHS Trust & University of Leicester, University of Liverpool .
Experimental human pneumococcal carriage (EHPC) is scientifically important because nasopharyngeal carriage of Streptococcus pneumoniae is both the major source of transmission and the prerequisite of invasive disease. A model of carriage will allow accurate determination of the immunological correlates of protection, the immunizing effect of carriage and the effect of host pressure on the pathogen in the nasopharyngeal niche. Further, methods of carriage detection useful in epidemiologic studies, including vaccine studies, can be compared. Aim We aim to develop an EHPC platform that is a safe and useful reproducible method that could be used to down-select candidate novel pneumococcal vaccines with prevention of carriage as a surrogate of vaccine induced immunity. It will work towards testing of candidate vaccines and descriptions of the mechanisms underlying EHPC and vaccine protection from carriage1. Current conjugate vaccines against pneumococcus protect children from invasive disease although new vaccines are urgently needed as the current vaccine does not confer optimal protection against non-bacteraemic pneumonia and there has been evidence of serotype replacement with non-vaccine serotypes2-4. Method We inoculate with S. pneumoniae suspended in 100 μl of saline. Safety is a major factor in the development of the EHPC model and is achieved through intensive volunteer screening and monitoring. A safety committee consisting of clinicians and scientists that are independent from the study provides objective feedback on a weekly basis. The bacterial inoculum is standardized and requires that no animal products are inoculated into volunteers (vegetable-based media and saline). The doses required for colonization (104-105) are much lower than those used in animal models (107)5. Detecting pneumococcal carriage is enhanced by a high volume (ideally >10 ml) nasal wash that is relatively mucus free. This protocol will deal with the most important parts of the protocol in turn. These are (a) volunteer selection, (b) pneumococcal inoculum preparation, (c) inoculation, (d) follow-up and (e) carriage detection. Results Our current protocol has been safe in over 100 volunteers at a range of doses using two different bacterial serotypes6. A dose ranging study using S. pneumoniae 6B and 23F is currently being conducted to determine the optimal inoculation dose for 50% carriage. A predicted 50% rate of carriage will allow the EHPC model to have high sensitivity for vaccine efficacy with small study numbers.
Infection, Issue 72, Medicine, Immmunology, Microbiology, Infectious Diseases, Anatomy, Physiology, Biomedical Engineering, Streptococcus pneumoniae, carriage, nasal wash, inoculation, human, vaccine studies, pneumonia, volunteer selection, clinical
Play Button
Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction
Authors: Maha Habib, Barbara D. Porter, Catherine Satzke.
Institutions: Murdoch Childrens Research Institute, The University of Melbourne.
There are over 90 different capsular serotypes of Streptococcus pneumoniae (the pneumococcus). As well as being a tool for understanding pneumococcal epidemiology, capsular serotyping can provide useful information for vaccine efficacy and impact studies. The Quellung reaction is the gold standard method for pneumococcal capsular serotyping. The method involves testing a pneumococcal cell suspension with pooled and specific antisera directed against the capsular polysaccharide. The antigen-antibody reactions are observed microscopically. The protocol has three main steps: 1) preparation of a bacterial cell suspension, 2) mixing of cells and antisera on a glass slide, and 3) reading the Quellung reaction using a microscope. The Quellung reaction is reasonably simple to perform and can be applied wherever a suitable microscope and antisera are available.
Immunology, Issue 84, Streptococcus pneumoniae, Quellung, serotyping, Neufeld, pneumococcus
Play Button
Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae
Authors: Alicja Puchta, Chris P. Verschoor, Tanja Thurn, Dawn M. E. Bowdish.
Institutions: McMaster University .
Nasopharyngeal colonization by Streptococcus pneumoniae is a prerequisite to invasion to the lungs or bloodstream1. This organism is capable of colonizing the mucosal surface of the nasopharynx, where it can reside, multiply and eventually overcome host defences to invade to other tissues of the host. Establishment of an infection in the normally lower respiratory tract results in pneumonia. Alternatively, the bacteria can disseminate into the bloodstream causing bacteraemia, which is associated with high mortality rates2, or else lead directly to the development of pneumococcal meningitis. Understanding the kinetics of, and immune responses to, nasopharyngeal colonization is an important aspect of S. pneumoniae infection models. Our mouse model of intranasal colonization is adapted from human models3 and has been used by multiple research groups in the study of host-pathogen responses in the nasopharynx4-7. In the first part of the model, we use a clinical isolate of S. pneumoniae to establish a self-limiting bacterial colonization that is similar to carriage events in human adults. The procedure detailed herein involves preparation of a bacterial inoculum, followed by the establishment of a colonization event through delivery of the inoculum via an intranasal route of administration. Resident macrophages are the predominant cell type in the nasopharynx during the steady state. Typically, there are few lymphocytes present in uninfected mice8, however mucosal colonization will lead to low- to high-grade inflammation (depending on the virulence of the bacterial species and strain) that will result in an immune response and the subsequent recruitment of host immune cells. These cells can be isolated by a lavage of the tracheal contents through the nares, and correlated to the density of colonization bacteria to better understand the kinetics of the infection.
Immunology, Issue 83, Streptococcus pneumoniae, Nasal lavage, nasopharynx, murine, flow cytometry, RNA, Quantitative PCR, recruited macrophages, neutrophils, T-cells, effector cells, intranasal colonization
Play Button
Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination
Authors: Barbara D. Porter, Belinda D. Ortika, Catherine Satzke.
Institutions: Murdoch Childrens Research Institute, The University of Melbourne.
Latex agglutination reagents are widely used in microbial diagnosis, identification and serotyping. Streptococcus pneumoniae (the pneumococcus) is a major cause of morbidity and mortality world-wide. Current vaccines target the pneumococcal capsule, and there are over 90 capsular serotypes. Serotyping pneumococcal isolates is therefore important for assessing the impact of vaccination programs and for epidemiological purposes. The World Health Organization has recommended latex agglutination as an alternative method to the ‘gold standard’ Quellung test for serotyping pneumococci. Latex agglutination is a relatively simple, quick and inexpensive method; and is therefore suitable for resource-poor settings as well as laboratories with high-volume workloads. Latex agglutination reagents can be prepared in-house utilizing commercially-sourced antibodies that are passively attached to latex particles. This manuscript describes a method of production and quality control of latex agglutination reagents, and details a sequential testing approach which is time- and cost-effective. This method of production and quality control may also be suitable for other testing purposes.
Immunology, Issue 91, Antisera, pneumococci, polysaccharide capsule, slide agglutination
Play Button
Investigating the Effects of Probiotics on Pneumococcal Colonization Using an In Vitro Adherence Assay
Authors: Eileen M. Dunne, Zheng Q. Toh, Mary John, Jayne Manning, Catherine Satzke, Paul Licciardi.
Institutions: Murdoch Childrens Research Institute, Murdoch Childrens Research Institute, The University of Melbourne, The University of Melbourne.
Adherence of Streptococcus pneumoniae (the pneumococcus) to the epithelial lining of the nasopharynx can result in colonization and is considered a prerequisite for pneumococcal infections such as pneumonia and otitis media. In vitro adherence assays can be used to study the attachment of pneumococci to epithelial cell monolayers and to investigate potential interventions, such as the use of probiotics, to inhibit pneumococcal colonization. The protocol described here is used to investigate the effects of the probiotic Streptococcus salivarius on the adherence of pneumococci to the human epithelial cell line CCL-23 (sometimes referred to as HEp-2 cells). The assay involves three main steps: 1) preparation of epithelial and bacterial cells, 2) addition of bacteria to epithelial cell monolayers, and 3) detection of adherent pneumococci by viable counts (serial dilution and plating) or quantitative real-time PCR (qPCR). This technique is relatively straightforward and does not require specialized equipment other than a tissue culture setup. The assay can be used to test other probiotic species and/or potential inhibitors of pneumococcal colonization and can be easily modified to address other scientific questions regarding pneumococcal adherence and invasion.
Immunology, Issue 86, Gram-Positive Bacterial Infections, Pneumonia, Bacterial, Lung Diseases, Respiratory Tract Infections, Streptococcus pneumoniae, adherence, colonization, probiotics, Streptococcus salivarius, In Vitro assays
Play Button
Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Authors: Jo-Ann McClure-Warnier, John M. Conly, Kunyan Zhang.
Institutions: Alberta Health Services / Calgary Laboratory Services / University of Calgary, University of Calgary, University of Calgary, University of Calgary, University of Calgary.
Staphylococcal Cassette Chromosome mec (SCCmec) typing is a very important molecular tool for understanding the epidemiology and clonal strain relatedness of methicillin-resistant Staphylococcus aureus (MRSA), particularly with the emerging outbreaks of community-associated MRSA (CA-MRSA) occurring on a worldwide basis. Traditional PCR typing schemes classify SCCmec by targeting and identifying the individual mec and ccr gene complex types, but require the use of many primer sets and multiple individual PCR experiments. We designed and published a simple multiplex PCR assay for quick-screening of major SCCmec types and subtypes I to V, and later updated it as new sequence information became available. This simple assay targets individual SCCmec types in a single reaction, is easy to interpret and has been extensively used worldwide. However, due to the sophisticated nature of the assay and the large number of primers present in the reaction, there is the potential for difficulties while adapting this assay to individual laboratories. To facilitate the process of establishing a MRSA SCCmec assay, here we demonstrate how to set up our multiplex PCR assay, and discuss some of the vital steps and procedural nuances that make it successful.
Infection, Issue 79, Microbiology, Genetics, Medicine, Cellular Biology, Molecular Biology, Biomedical Engineering, Bacteria, Bacterial Infections and Mycoses, Life Sciences (General), Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcal cassette chromosome mec (SCCmec), SCCmec typing, Multiplex PCR, PCR, sequencing
Play Button
Modeling Mucosal Candidiasis in Larval Zebrafish by Swimbladder Injection
Authors: Remi L. Gratacap, Audrey C. Bergeron, Robert T. Wheeler.
Institutions: University of Maine, University of Maine.
Early defense against mucosal pathogens consists of both an epithelial barrier and innate immune cells. The immunocompetency of both, and their intercommunication, are paramount for the protection against infections. The interactions of epithelial and innate immune cells with a pathogen are best investigated in vivo, where complex behavior unfolds over time and space. However, existing models do not allow for easy spatio-temporal imaging of the battle with pathogens at the mucosal level. The model developed here creates a mucosal infection by direct injection of the fungal pathogen, Candida albicans, into the swimbladder of juvenile zebrafish. The resulting infection enables high-resolution imaging of epithelial and innate immune cell behavior throughout the development of mucosal disease. The versatility of this method allows for interrogation of the host to probe the detailed sequence of immune events leading to phagocyte recruitment and to examine the roles of particular cell types and molecular pathways in protection. In addition, the behavior of the pathogen as a function of immune attack can be imaged simultaneously by using fluorescent protein-expressing C. albicans. Increased spatial resolution of the host-pathogen interaction is also possible using the described rapid swimbladder dissection technique. The mucosal infection model described here is straightforward and highly reproducible, making it a valuable tool for the study of mucosal candidiasis. This system may also be broadly translatable to other mucosal pathogens such as mycobacterial, bacterial or viral microbes that normally infect through epithelial surfaces.
Immunology, Issue 93, Zebrafish, mucosal candidiasis, mucosal infection, epithelial barrier, epithelial cells, innate immunity, swimbladder, Candida albicans, in vivo.
Play Button
Methods to Assess Subcellular Compartments of Muscle in C. elegans
Authors: Christopher J. Gaffney, Joseph J. Bass, Thomas F. Barratt, Nathaniel J. Szewczyk.
Institutions: University of Nottingham.
Muscle is a dynamic tissue that responds to changes in nutrition, exercise, and disease state. The loss of muscle mass and function with disease and age are significant public health burdens. We currently understand little about the genetic regulation of muscle health with disease or age. The nematode C. elegans is an established model for understanding the genomic regulation of biological processes of interest. This worm’s body wall muscles display a large degree of homology with the muscles of higher metazoan species. Since C. elegans is a transparent organism, the localization of GFP to mitochondria and sarcomeres allows visualization of these structures in vivo. Similarly, feeding animals cationic dyes, which accumulate based on the existence of a mitochondrial membrane potential, allows the assessment of mitochondrial function in vivo. These methods, as well as assessment of muscle protein homeostasis, are combined with assessment of whole animal muscle function, in the form of movement assays, to allow correlation of sub-cellular defects with functional measures of muscle performance. Thus, C. elegans provides a powerful platform with which to assess the impact of mutations, gene knockdown, and/or chemical compounds upon muscle structure and function. Lastly, as GFP, cationic dyes, and movement assays are assessed non-invasively, prospective studies of muscle structure and function can be conducted across the whole life course and this at present cannot be easily investigated in vivo in any other organism.
Developmental Biology, Issue 93, Physiology, C. elegans, muscle, mitochondria, sarcomeres, ageing
Play Button
Using the Overlay Assay to Qualitatively Measure Bacterial Production of and Sensitivity to Pneumococcal Bacteriocins
Authors: Natalie Maricic, Suzanne Dawid.
Institutions: University of Michigan, University of Michigan.
Streptococcus pneumoniae colonizes the highly diverse polymicrobial community of the nasopharynx where it must compete with resident organisms. We have shown that bacterially produced antimicrobial peptides (bacteriocins) dictate the outcome of these competitive interactions. All fully-sequenced pneumococcal strains harbor a bacteriocin-like peptide (blp) locus. The blp locus encodes for a range of diverse bacteriocins and all of the highly conserved components needed for their regulation, processing, and secretion. The diversity of the bacteriocins found in the bacteriocin immunity region (BIR) of the locus is a major contributor of pneumococcal competition. Along with the bacteriocins, immunity genes are found in the BIR and are needed to protect the producer cell from the effects of its own bacteriocin. The overlay assay is a quick method for examining a large number of strains for competitive interactions mediated by bacteriocins. The overlay assay also allows for the characterization of bacteriocin-specific immunity, and detection of secreted quorum sensing peptides. The assay is performed by pre-inoculating an agar plate with a strain to be tested for bacteriocin production followed by application of a soft agar overlay containing a strain to be tested for bacteriocin sensitivity. A zone of clearance surrounding the stab indicates that the overlay strain is sensitive to the bacteriocins produced by the pre-inoculated strain. If no zone of clearance is observed, either the overlay strain is immune to the bacteriocins being produced or the pre-inoculated strain does not produce bacteriocins. To determine if the blp locus is functional in a given strain, the overlay assay can be adapted to evaluate for peptide pheromone secretion by the pre-inoculated strain. In this case, a series of four lacZ-reporter strains with different pheromone specificity are used in the overlay.
Infectious Diseases, Issue 91, bacteriocins, antimicrobial peptides, blp locus, bacterial competition, Streptococcus pneumoniae, overlay assay
Play Button
Cortical Source Analysis of High-Density EEG Recordings in Children
Authors: Joe Bathelt, Helen O'Reilly, Michelle de Haan.
Institutions: UCL Institute of Child Health, University College London.
EEG is traditionally described as a neuroimaging technique with high temporal and low spatial resolution. Recent advances in biophysical modelling and signal processing make it possible to exploit information from other imaging modalities like structural MRI that provide high spatial resolution to overcome this constraint1. This is especially useful for investigations that require high resolution in the temporal as well as spatial domain. In addition, due to the easy application and low cost of EEG recordings, EEG is often the method of choice when working with populations, such as young children, that do not tolerate functional MRI scans well. However, in order to investigate which neural substrates are involved, anatomical information from structural MRI is still needed. Most EEG analysis packages work with standard head models that are based on adult anatomy. The accuracy of these models when used for children is limited2, because the composition and spatial configuration of head tissues changes dramatically over development3.  In the present paper, we provide an overview of our recent work in utilizing head models based on individual structural MRI scans or age specific head models to reconstruct the cortical generators of high density EEG. This article describes how EEG recordings are acquired, processed, and analyzed with pediatric populations at the London Baby Lab, including laboratory setup, task design, EEG preprocessing, MRI processing, and EEG channel level and source analysis. 
Behavior, Issue 88, EEG, electroencephalogram, development, source analysis, pediatric, minimum-norm estimation, cognitive neuroscience, event-related potentials 
Play Button
Bronchoalveolar Lavage (BAL) for Research; Obtaining Adequate Sample Yield
Authors: Andrea M. Collins, Jamie Rylance, Daniel G. Wootton, Angela D. Wright, Adam K. A. Wright, Duncan G. Fullerton, Stephen B. Gordon.
Institutions: National Institute for Health Research, Royal Liverpool and Broadgreen University Hospital Trust, Liverpool School of Tropical Medicine, University of Liverpool, Royal Liverpool and Broadgreen University Hospital Trust, University Hospital Aintree.
We describe a research technique for fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) using manual hand held suction in order to remove nonadherent cells and lung lining fluid from the mucosal surface. In research environments, BAL allows sampling of innate (lung macrophage), cellular (B- and T- cells), and humoral (immunoglobulin) responses within the lung. BAL is internationally accepted for research purposes and since 1999 the technique has been performed in > 1,000 subjects in the UK and Malawi by our group. Our technique uses gentle hand-held suction of instilled fluid; this is designed to maximize BAL volume returned and apply minimum shear force on ciliated epithelia in order to preserve the structure and function of cells within the BAL fluid and to preserve viability to facilitate the growth of cells in ex vivo culture. The research technique therefore uses a larger volume instillate (typically in the order of 200 ml) and employs manual suction to reduce cell damage. Patients are given local anesthetic, offered conscious sedation (midazolam), and tolerate the procedure well with minimal side effects. Verbal and written subject information improves tolerance and written informed consent is mandatory. Safety of the subject is paramount. Subjects are carefully selected using clear inclusion and exclusion criteria. This protocol includes a description of the potential risks, and the steps taken to mitigate them, a list of contraindications, pre- and post-procedure checks, as well as precise bronchoscopy and laboratory techniques.
Medicine, Issue 85, Research bronchoscopy, bronchoalveolar lavage (BAL), fiberoptic bronchoscopy, lymphocyte, macrophage
Play Button
A Proboscis Extension Response Protocol for Investigating Behavioral Plasticity in Insects: Application to Basic, Biomedical, and Agricultural Research
Authors: Brian H. Smith, Christina M. Burden.
Institutions: Arizona State University.
Insects modify their responses to stimuli through experience of associating those stimuli with events important for survival (e.g., food, mates, threats). There are several behavioral mechanisms through which an insect learns salient associations and relates them to these events. It is important to understand this behavioral plasticity for programs aimed toward assisting insects that are beneficial for agriculture. This understanding can also be used for discovering solutions to biomedical and agricultural problems created by insects that act as disease vectors and pests. The Proboscis Extension Response (PER) conditioning protocol was developed for honey bees (Apis mellifera) over 50 years ago to study how they perceive and learn about floral odors, which signal the nectar and pollen resources a colony needs for survival. The PER procedure provides a robust and easy-to-employ framework for studying several different ecologically relevant mechanisms of behavioral plasticity. It is easily adaptable for use with several other insect species and other behavioral reflexes. These protocols can be readily employed in conjunction with various means for monitoring neural activity in the CNS via electrophysiology or bioimaging, or for manipulating targeted neuromodulatory pathways. It is a robust assay for rapidly detecting sub-lethal effects on behavior caused by environmental stressors, toxins or pesticides. We show how the PER protocol is straightforward to implement using two procedures. One is suitable as a laboratory exercise for students or for quick assays of the effect of an experimental treatment. The other provides more thorough control of variables, which is important for studies of behavioral conditioning. We show how several measures for the behavioral response ranging from binary yes/no to more continuous variable like latency and duration of proboscis extension can be used to test hypotheses. And, we discuss some pitfalls that researchers commonly encounter when they use the procedure for the first time.
Neuroscience, Issue 91, PER, conditioning, honey bee, olfaction, olfactory processing, learning, memory, toxin assay
Play Button
Sublingual Immunotherapy as an Alternative to Induce Protection Against Acute Respiratory Infections
Authors: Natalia Muñoz-Wolf, Analía Rial, José M. Saavedra, José A. Chabalgoity.
Institutions: Universidad de la República, Trinity College Dublin.
Sublingual route has been widely used to deliver small molecules into the bloodstream and to modulate the immune response at different sites. It has been shown to effectively induce humoral and cellular responses at systemic and mucosal sites, namely the lungs and urogenital tract. Sublingual vaccination can promote protection against infections at the lower and upper respiratory tract; it can also promote tolerance to allergens and ameliorate asthma symptoms. Modulation of lung’s immune response by sublingual immunotherapy (SLIT) is safer than direct administration of formulations by intranasal route because it does not require delivery of potentially harmful molecules directly into the airways. In contrast to intranasal delivery, side effects involving brain toxicity or facial paralysis are not promoted by SLIT. The immune mechanisms underlying SLIT remain elusive and its use for the treatment of acute lung infections has not yet been explored. Thus, development of appropriate animal models of SLIT is needed to further explore its potential advantages. This work shows how to perform sublingual administration of therapeutic agents in mice to evaluate their ability to protect against acute pneumococcal pneumonia. Technical aspects of mouse handling during sublingual inoculation, precise identification of sublingual mucosa, draining lymph nodes and isolation of tissues, bronchoalveolar lavage and lungs are illustrated. Protocols for single cell suspension preparation for FACS analysis are described in detail. Other downstream applications for the analysis of the immune response are discussed. Technical aspects of the preparation of Streptococcus pneumoniae inoculum and intranasal challenge of mice are also explained. SLIT is a simple technique that allows screening of candidate molecules to modulate lungs’ immune response. Parameters affecting the success of SLIT are related to molecular size, susceptibility to degradation and stability of highly concentrated formulations.
Medicine, Issue 90, Sublingual immunotherapy, Pneumonia, Streptococcus pneumoniae, Lungs, Flagellin, TLR5, NLRC4
Play Button
Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns
Authors: Rangaraj M. Rangayyan, Shantanu Banik, J.E. Leo Desautels.
Institutions: University of Calgary , University of Calgary .
We demonstrate methods for the detection of architectural distortion in prior mammograms of interval-cancer cases based on analysis of the orientation of breast tissue patterns in mammograms. We hypothesize that architectural distortion modifies the normal orientation of breast tissue patterns in mammographic images before the formation of masses or tumors. In the initial steps of our methods, the oriented structures in a given mammogram are analyzed using Gabor filters and phase portraits to detect node-like sites of radiating or intersecting tissue patterns. Each detected site is then characterized using the node value, fractal dimension, and a measure of angular dispersion specifically designed to represent spiculating patterns associated with architectural distortion. Our methods were tested with a database of 106 prior mammograms of 56 interval-cancer cases and 52 mammograms of 13 normal cases using the features developed for the characterization of architectural distortion, pattern classification via quadratic discriminant analysis, and validation with the leave-one-patient out procedure. According to the results of free-response receiver operating characteristic analysis, our methods have demonstrated the capability to detect architectural distortion in prior mammograms, taken 15 months (on the average) before clinical diagnosis of breast cancer, with a sensitivity of 80% at about five false positives per patient.
Medicine, Issue 78, Anatomy, Physiology, Cancer Biology, angular spread, architectural distortion, breast cancer, Computer-Assisted Diagnosis, computer-aided diagnosis (CAD), entropy, fractional Brownian motion, fractal dimension, Gabor filters, Image Processing, Medical Informatics, node map, oriented texture, Pattern Recognition, phase portraits, prior mammograms, spectral analysis
Play Button
Using Bioluminescent Imaging to Investigate Synergism Between Streptococcus pneumoniae and Influenza A Virus in Infant Mice
Authors: Kirsty R. Short, Dimitri A. Diavatopoulos, Patrick C. Reading, Lorena E. Brown, Kelly L. Rogers, Richard A. Strugnell, Odilia L.C. Wijburg.
Institutions: University of Melbourne, Radboud University Nijmegen Medical Centre, The Walter and Eliza Hall Institute for Medical Research.
During the 1918 influenza virus pandemic, which killed approximately 50 million people worldwide, the majority of fatalities were not the result of infection with influenza virus alone. Instead, most individuals are thought to have succumbed to a secondary bacterial infection, predominately caused by the bacterium Streptococcus pneumoniae (the pneumococcus). The synergistic relationship between infections caused by influenza virus and the pneumococcus has subsequently been observed during the 1957 Asian influenza virus pandemic, as well as during seasonal outbreaks of the virus (reviewed in 1, 2). Here, we describe a protocol used to investigate the mechanism(s) that may be involved in increased morbidity as a result of concurrent influenza A virus and S. pneumoniae infection. We have developed an infant murine model to reliably and reproducibly demonstrate the effects of influenza virus infection of mice colonised with S. pneumoniae. Using this protocol, we have provided the first insight into the kinetics of pneumococcal transmission between co-housed, neonatal mice using in vivo imaging 3.
Infection, Issue 50, Bioluminescent imaging, influenza A virus, Streptococcus pneumoniae, mice, intranasal infection, otitis media, co-infections
Play Button
Interview: Glycolipid Antigen Presentation by CD1d and the Therapeutic Potential of NKT cell Activation
Authors: Mitchell Kronenberg.
Institutions: La Jolla Institute for Allergy and Immunology.
Natural Killer T cells (NKT) are critical determinants of the immune response to cancer, regulation of autioimmune disease, clearance of infectious agents, and the development of artheriosclerotic plaques. In this interview, Mitch Kronenberg discusses his laboratory's efforts to understand the mechanism through which NKT cells are activated by glycolipid antigens. Central to these studies is CD1d - the antigen presenting molecule that presents glycolipids to NKT cells. The advent of CD1d tetramer technology, a technique developed by the Kronenberg lab, is critical for the sorting and identification of subsets of specific glycolipid-reactive T cells. Mitch explains how glycolipid agonists are being used as therapeutic agents to activate NKT cells in cancer patients and how CD1d tetramers can be used to assess the state of the NKT cell population in vivo following glycolipid agonist therapy. Current status of ongoing clinical trials using these agonists are discussed as well as Mitch's prediction for areas in the field of immunology that will have emerging importance in the near future.
Immunology, Issue 10, Natural Killer T cells, NKT cells, CD1 Tetramers, antigen presentation, glycolipid antigens, CD1d, Mucosal Immunity, Translational Research
Play Button
Ole Isacson: Development of New Therapies for Parkinson's Disease
Authors: Ole Isacson.
Institutions: Harvard Medical School.
Medicine, Issue 3, Parkinson' disease, Neuroscience, dopamine, neuron, L-DOPA, stem cell, transplantation
Copyright © JoVE 2006-2015. All Rights Reserved.
Policies | License Agreement | ISSN 1940-087X
simple hit counter

What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.